The Autoimmune Diet: Are You Missing This Key Sunshine Nutrient?

The human immune system is a marvel of biological engineering, a silent and sophisticated network of defence molecules that work tirelessly to neutralise external threats like viruses and bacteria with incredible precision. But despite its usual accuracy, on occasion, this army of defence cells can go awry, making mistakes that significantly impact the body, resulting in a range of autoimmune conditions.

What is autoimmunity?

Autoimmunity is when the immune system, which normally protects the body from foreign invaders, loses the ability to distinguish ‘self’ from ‘non-self’ and mistakenly attacks the body’s healthy cells. It wrongly flags perfectly healthy cells as threats and launches an inflammatory attack, causing damage that can manifest in many ways, depending on which part of the body is targeted:

Rheumatoid Arthritis: The immune system attacks the lining of the joints.
Multiple Sclerosis: The protective coating of nerve cells is damaged.
Systemic Lupus Erythematosus: A systemic condition that can affect the skin, joints, kidneys, and brain.
Type 1 Diabetes: The insulin-producing cells in the pancreas are destroyed.
Inflammatory Bowel Disease: Chronic inflammation occurs in the digestive tract.

This is just a small sample, with over eighty different autoimmune diseases now identified,¹ intense research is focused on how certain nutrients can help maintain the immune system's delicate balance and communication.

Enter Vitamin D

It is universally recognised that vitamin D contributes to normal immune function. This connection happens at a cellular level, where key immune cells, such as T-cells and B-cells, are equipped with vitamin D receptors (docking sites).

Once vitamin D binds to these sites, it helps ensure a balanced response from these immune cells, behaving less like a simple switch and more like the conductor of an orchestra. A key aspect of this function is its role in cellular communication, where it helps manage the pathways involving cytokines as part of a normal immune response.²

This idea of Vitamin D as an immune conductor isn't just a theory; it's backed up by what scientists have identified around the world. ^3,4 Their investigations have revealed that autoimmune conditions become more frequent the further people live from the equator, where sunlight is less intense year-round.⁵ Since our bodies make most of our Vitamin D from sun exposure, this was an important finding, prompting scientists to explore further the link between vitamin D levels and maintaining a balanced immune system.

Is There a Link to Autoimmunity?

In one of the most powerful studies, scientists analysed over seven million U.S. military personnel. Their observations uncovered an association between vitamin D status and immune-related health outcomes, such as multiple sclerosis.⁶

In a further study, researchers tracked over 25,000 adults for five years, giving one group daily vitamin D and the other a placebo.⁷ Results showed a 22% lower rate of new autoimmune diagnoses among the people taking vitamin D. These positive findings reinforce current knowledge that vitamin D makes an important contribution to normal immune function.

Eating For Immune Balance

To optimise your immune health, it's essential to consume a steady supply of nutrient-rich foods through your diet. Vitamin C, found in citrus fruits, bell peppers, and broccoli, is a well-known antioxidant that is known to support normal immune function. Equally important is zinc, present in nuts, seeds, and lean protein, all of which make an important contribution to the normal development and function of immune cells.

Nourishing your gut microbiome with fibre-rich foods, like vegetables, lentils, and whole grains, is another important strategy for building immune resilience. Fibre acts as fuel for beneficial gut bacteria, which are shown to play a vital role in supporting a well-regulated immune response.⁸

Foods rich in polyphenols, such as berries, dark chocolate, and green tea, also contribute to a healthy gut environment, supporting the integrity of the gut lining, which acts as a critical protective barrier.⁹

By consistently incorporating a variety of whole foods rich in these and other key nutrients, you provide your body with the building blocks necessary for its daily immune activities.

Sun, Food or Supplements?

In regions such as Northern Europe, the northern latitude makes it challenging to produce sufficient vitamin D from sunlight alone, particularly between October and March, when the sun is not strong enough for our skin to synthesise the vitamin D we require. Dietary sources of vitamin D are also very limited, e.g, oily fish, egg yolks and mushrooms exposed to UV light. Furthermore, optimising your vitamin D levels is one of the easiest, safest, most inexpensive, and impactful ways to enhance health and support immune function, especially when sun exposure is limited.

Which Form of Vitamin D is Best?

Both vitamin D2 and vitamin D3 are available in supplement form, but vitamin D3, the cholecalciferol form that your body naturally produces from sunlight, is shown to be the most effective at raising vitamin D levels in the blood. ¹⁰

Neutrient D3+K2 is an advanced sublingual vegan spray delivering maximised absorption of bioactive forms of vitamins D3 and K2, supporting both immune function and bone health.

GET NEUTRIENT D3 + K2

Written by: Jacqueline Newson BSc (Hons) Nutritional Therapy

REFERENCES

Conrad N et al. Incidence, prevalence, and co-occurrence of autoimmune disorders over time and by age, sex, and socioeconomic status: a population-based cohort study of 22 million individuals in the UK. The Lancet 2023; 401,10391: 1878-1890.
Kraus A U et al. Monocytic Cytokines in Autoimmune Polyglandular Syndrome Type 2 Are Modulated by Vitamin D and HLA-DQ. Front. Immunol., 2020;11.| https://doi.org/10.3389/fimmu.2020.583709.
Grant WB. The role of geographical ecological studies in identifying diseases linked to UVB exposure and/or vitamin D. Dermatoendocrinol. 2016 Jan 8;8(1):e1137400. doi: 10.1080/19381980.2015.1137400. PMID: 27195055; PMCID: PMC4862381.
Schwalfenberg GK. Solar radiation and vitamin D: mitigating environmental factors in autoimmune disease. J Environ Public Health. 2012;2012:619381. doi: 10.1155/2012/619381. Epub 2012 Jan 11. PMID: 22523507; PMCID: PMC3317188.
Cantorna MT. Vitamin D and autoimmunity: is vitamin D status an environmental factor affecting autoimmune disease prevalence? Proc Soc Exp Biol Med. 2000 Mar;223(3):230-3. doi: 10.1046/j.1525-1373.2000.22333.x. PMID: 10719834.
Munger KL, Levin LI, Hollis BW, Howard NS, Ascherio A. Serum 25-Hydroxyvitamin D Levels and Risk of Multiple Sclerosis. JAMA. 2006;296(23):2832–2838. doi:10.1001/jama.296.23.2832.
Hahn J, Cook NR, Alexander EK, Friedman S, Walter J, Bubes V, Kotler G, Lee IM, Manson JE, Costenbader KH. Vitamin D and marine omega 3 fatty acid supplementation and incident autoimmune disease: VITAL randomized controlled trial. BMJ. 2022 Jan 26;376:e066452. doi: 10.1136/bmj-2021-066452. PMID: 35082139; PMCID: PMC8791065.
Zheng, D., Liwinski, T., & Elinav, E. (2020). The Interplay between the Gut Microbiome and the Immune System in the Context of Infectious Diseases, Autoimmunity, and Cancer. Frontiers in Immunology, 11, 287. https://doi.org/10.3389/fimmu.2020.00287.
Biasi, F., De Cunto, G., & Leonarduzzi, G. (2022). The impact of polyphenols on the gut microbiota and intestinal barrier function: A review. Frontiers in Immunology, 13, 928328. https://doi.org/10.3389/fimmu.2022.928328.
Tripkovic, L., Lambert, H., Hart, K., Smith, C. P., Bucca, G., Penson, S., Chope, G., Hyppönen, E., Lada, M., Vail, A., & Lanham-New, S. A. (2012). Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. The American Journal of Clinical Nutrition, 95(6), 1357–1364. https://doi.org/10.3945/ajcn.111.031070.